Question

Given a device instance ID for a network card, I would like to know its MAC address. Example device instance ID on my system for integrated Intel Gigabit card:

PCI\VEN_8086&DEV_10CC&SUBSYS_00008086&REV_00\3&33FD14CA&0&C8

So far, the algorithm I have used works as follows:

1. Call SetupDiGetClassDevs with DIGCF_DEVICEINTERFACE.
2. Call SetupDiEnumDeviceInfo to get the returned device in a SP_DEVINFO_DATA.
3. Call SetupDiEnumDeviceInterfaces with GUID_NDIS_LAN_CLASS to get a device interface.
4. Call SetupDiGetDeviceInterfaceDetail for this returned device interface. This gets us the device path as a string: \\?\pci#ven_8086&dev_10cc&subsys_00008086&rev_00#3&33fd14ca&0&c8#{ad498944-762f-11d0-8dcb-00c04fc3358c}\{28fd5409-15bd-4c06-b62f-004d3a06f852}
5. At this point we have an address to the network card driver’s interface. Open it with CreateFile using the result from #4.
6. Call DeviceIoControl with IOCTL_NDIS_QUERY_GLOBAL_STATS and OID of OID_802_3_PERMANENT_ADDRESS to get the MAC address.

This usually works, and has been used successfully on quite a large number of machines. However, it appears that a very select few machines have network drivers that aren’t responding properly to the DeviceIoControl request in step #6; the problem persists even after updating network card drivers to the latest. These are newer, Windows 7-based computers. Specifically, DeviceIoControl completes successfully, but returns zero bytes instead of the expected six bytes containing the MAC address.

A clue seems to be on the MSDN page for IOCTL_NDIS_QUERY_GLOBAL_STATS:

This IOCTL will be deprecated in later operating system releases. You
should use WMI interfaces to query miniport driver information. For
more information see, NDIS Support for WMI.

— perhaps newer network card drivers are no longer implementing this IOCTL?

So, how should I get this working? Is it possible there’s an oversight in my approach and I’m doing something slightly wrong? Or do I need to take a much more different approach? Some alternate approaches seem to include:

• Query Win32_NetworkAdapter WMI class: provides needed information but rejected due to horrible performance. See Fast replacement for Win32_NetworkAdapter WMI class for getting MAC address of local computer
• Query MSNdis_EthernetPermanentAddress WMI class: appears to be the WMI replacement for IOCTL_NDIS_QUERY_GLOBAL_STATS and queries the OID directly from the driver – and this one works on the troublesome network driver. Unfortunately, the returned class instances only provide the MAC address and the InstanceName, which is a localized string like Intel(R) 82567LM-2 Gigabit Network Connection. Querying MSNdis_EnumerateAdapter yields a list which relates the InstanceName to a DeviceName, like \DEVICE\{28FD5409-15BD-4C06-B62F-004D3A06F852}. I’m not sure how to go from the DeviceName to the plug-and-play device instance ID (PCI\VEN_8086......).
• Call GetAdaptersAddresses or GetAdaptersInfo (deprecated). The only non-localized identifier I can find in the return value is the adapter name, which is a string like {28FD5409-15BD-4C06-B62F-004D3A06F852} – same as the DeviceName returned by the WMI NDIS classes. So again, I can’t figure out how to relate it to the device instance ID. I’m not sure if it would work 100% of the time either – e.g. for adapters without TCP/IP protocol configured.
• NetBIOS method: requires specific protocols to be set up on the card so won’t work 100% of time. Generally seems hack-ish, and not a way to relate to device instance ID anyway that I know of. I’d reject this approach.
• UUID generation method: rejected for reasons I won’t elaborate on here.

It seems like if I could find a way to get the “GUID” for the card from the device instance ID, I’d be well on my way with one of the remaining two ways of doing things. But I haven’t figured out how yet. Otherwise, the WMI NDIS approach would seem most promising.

Getting a list of network cards and MAC addresses is easy, and there are several ways of doing it. Doing it in a fast way that lets me relate it to the device instance ID is apparently hard…

EDIT: Sample code of the IOCTL call if it helps anyone (ignore the leaked hFile handle):

HANDLE hFile = CreateFile(dosDevice.c_str(), 0, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, NULL);
if (hFile == INVALID_HANDLE_VALUE) {
    DWORD err = GetLastError();
    wcout << "GetMACAddress: CreateFile on " << dosDevice << " failed." << endl;
    return MACAddress();
}
BYTE address[6];
DWORD oid = OID_802_3_PERMANENT_ADDRESS, returned = 0;
//this fails too: DWORD oid = OID_802_3_CURRENT_ADDRESS, returned = 0;
if (!DeviceIoControl(hFile, IOCTL_NDIS_QUERY_GLOBAL_STATS, &oid, sizeof(oid), address, 6, &returned, NULL)) {
    DWORD err = GetLastError();
    wcout << "GetMACAddress: DeviceIoControl on " << dosDevice << " failed." << endl;
    return MACAddress();
}
if (returned != 6) {
    wcout << "GetMACAddress: invalid address length of " << returned << "." << endl;
    return MACAddress();
}

The code fails, printing:

GetMACAddress: invalid address length of 0.

So the DeviceIoControl returns non-zero indicating success, but then returns zero bytes.

Answer 1

I wound up using SetupDiGetDeviceRegistryProperty to read SPDRP_FRIENDLYNAME. If that’s not found, then I read SPDRP_DEVICEDESC instead. Ultimately, this gets me a string like “VirtualBox Host-Only Ethernet Adapter #2”. I then match this against the InstanceName property in the WMI NDIS classes (MSNdis_EthernetPermanentAddress WMI class). Both properties must be read in case there are multiple adapters sharing the same driver (i.e. “#2”, “#3”, etc.) – if there’s only one adapter then SPDRP_FRIENDLYNAME isn’t available, but if there is more than one then SPDRP_FRIENDLYNAME is required to differentiate them.

The method makes me a little nervous because I’m comparing what seems like a localized string, and there’s no documentation that I’ve found that guarantees what I’m doing will always work. Unfortunately, I haven’t found any better ways that are documented to work, either.

A couple other alternate methods involve groveling in undocumented registry locations. One method is spencercw’s method, and the other would be to read SPDRP_DRIVER, which is the name of a subkey under HKLM\SYSTEM\CurrentControlSet\Control\Class. Underneath the driver key, look for the Linkage\Export value which then seems like it could be matched to the DeviceName property of the MSNdis_EnumerateAdapter class. But there’s no documentation I could find that says these values can be legally matched. Furthermore, the only documentation I found about Linkage\Export was from the Win2000 registry reference and explicitly said that applications shouldn’t rely on it.

Another method would be to look at my original question, step 4: “SetupDiGetDeviceInterfaceDetail for this returned device interface”. The device interface path actually can be used to reconstruct the device path. Start with device interface path: \\?\pci#ven_8086&dev_10cc&subsys_00008086&rev_00#3&33fd14ca&0&c8#{ad498944-762f-11d0-8dcb-00c04fc3358c}\{28fd5409-15bd-4c06-b62f-004d3a06f852}. Then, remove everything before the final slash, leaving you with: {28fd5409-15bd-4c06-b62f-004d3a06f852}. Finally, prepend \Device\ to this string and match it against the WMI NDIS classes. Again, however, this seems to be undocumented and relying on an implementation detail of a device interface path.

In the end, the other methods I investigated had their own undocumented complications that sounded at least as serious as matching the SPDRP_FRIENDLYNAME / SPDRP_DEVICEDESC strings. So I opted for the simpler approach, which was to just match those strings against the WMI NDIS classes.